[fpc-pascal] Challenging port of Borland Pascal program to FPC

[Jeff Wormsley]

John Youngquist wrote:
> I would like to port the program as is, but eventually get a PCI 48 
> I/O line card to escape
> the ISA bus and also talk USB as well. Getting it to run on later 
> versions of Windows might
> be useful. This program controls a machine on a single purpose 
> computer. Windows is used
> to handle files, networks, and little else. Most of the time only this 
> program is run. A port to
> Linux might be acceptable if that would solve some problems.
>
> Are these insurmountable obstacles?
Probably not if you're willing to spend a ton of time and money, but you 
might be better off moving the bulk of this system off of a PC and on to 
a dedicated micro controller board, and just using a PC to handle UI and 
files/network and things that don't have any real time requirements.  
The STM-32 Cortex chips in the 144 pin package should probably have 
enough I/O and speed to do what you want, with built in ram/rom.  
Coupled with FreeRTOS, you can have a quite capable system for not a lot 
of money (you should be able to build a board to replace the PC hardware 
for a couple of hundred dollars, depending on how sophisticated the 48 
port I/O board is).

I'm surprised the current system ran properly on a Win98 DOS box, 
considering how badly Windows messes up real time (those 10ms breaks 
should have probably been much longer on occasion when the Windows 
kernel was busy doing stuff with interrupts disabled).  Until I found 
out how to use the multimedia timers, I couldn't get better than 55ms 
response out of Windows, even from a DOS box.

Jeff.